I have the 806 and I use a sony cooling fan with adjustible speeds. I tried running it about an hour without the fan and it ran warm. The sound is great. I still have my Onkyo tx ds787 and that runs cool. I think people do more harm if they plug in a unit that was just delivered from a cold UPS truck. I always let mine warm up to room temperature an I have had great luck with all my purchases except for two Athena ps 6000 subwoofers.Both amps failed within a year.